This invention is directed generally to antenna, and more particularly to a novel feed network integrated with an array of antenna elements and a shaped reflector.
Local multipoint distribution service (LMDS) is a broadband wireless point-to-multipoint communication system that can be used to provide digital two-way voice, data, Internet, and video services. In such a definition, xe2x80x9clocalxe2x80x9d denotes that propagation characteristics of signals in this system limit the potential coverage area to that of a single cell site. For example, field trials conducted in metropolitan centers limit the range of transmitters in these systems to approximately five miles. xe2x80x9cMultipointxe2x80x9d indicates that base station signals are transmitted in a point-to-multipoint or broadcast method; whereas, the wireless return path, from subscriber to the base station, is a point-to-point transmission. xe2x80x9cDistributionxe2x80x9d refers to the distribution of signals, which may consist of simultaneous voice, data, Internet, and video traffic. xe2x80x9cServicexe2x80x9d implies the subscriber nature of the relationship between the operator and the customer or the services offered through an LMDS network that are entirely dependent on the operator""s choice of business.
For LMDS, or other similar point-to-multipoint applications, base station antennas are required to deliver services over one or more sectors within a cell site. To meet this requirement, antennas should have reasonably high gain characteristics and meet a specified azimuth beamwidth to provide the desired sector coverage. Furthermore, it is desirable to provide a relatively rugged and reliable antenna structure since such systems are often deployed in an urban environment. Ideally, such an antenna structure should have relatively simple and few parts and be relatively easy and inexpensive to manufacture and to install and maintain in the field.
Therefore, a significant need exists in the art for an improved antenna that has desirable azimuth beamwidth characteristics that has relatively few and uncomplicated parts. It is also desirable that any such antenna be straightforward and inexpensive to manufacture and install and maintain. It is s till further desirable, that such an improved antenna has applicability within an LMDS system.